The present invention is directed to ready to use hard surface cleaning compositions. More particularly the present invention is directed to alkaline cleaning and sanitizing compositions which are essentially free of chelating agents based on organic acid compound, especially nitrogen containing chelating agents, which composition is particularly directed for the effective removal of soap scum stains on hard surfaces which comprises. The compositions of the present invention are particularly adapted to be used as a xe2x80x98ready-to-usexe2x80x99 type composition, as well as in a non-pressurized container which is supplied with a hand pumpable trigger spray apparatus. The present invention is also directed to the use of such a composition in the cleaning or sanitization of a hard surface, as well as methods for producing such compositions.
As is known to the art, hard surfaces associated with lavatories (including lavatory appliances especially washing sinks, shower stalls and bathtubs) are typically prone to accumulate soap scum stains. Such surfaces are usually made of materials such as tiles (glazed and unglazed), marble, ceramics and enameled porcelain surfaces. The latter include European porcelain surfaces which generally are more prone to damage or discoloration due to the use of particularly aggressive cleaning compositions, especially those with low pH values. Thus, acid cleaning compositions are desirably to be avoided for use in cleaning such surfaces. The use of alkaline cleaning compositions are therefore preferred, however most alkaline cleaning compositions are not sufficiently satisfactory to effectively clean soap scum stains from surfaces. This shortcoming has been met in the art by the require the inclusion of an effective amount of a chelating agent which is typically based on one or more organic acid compounds, especially nitrogen containing organic compounds which include a plurality of carboxylic acid groups. Such chelating agents include gluconic acid, tartartic acid, citric acid, oxalic acid, lactic acid, ethylenediamine mono-, di- or tri-acetic acid, ethylenedianinetetraacetic acid, N-hydroxyethylethylenediarnine triacetic acid, nitrilotriacetic acid, diethylene triamine pentaacetic acid, and their water soluble salts of these compounds, especially the alkali metal salts and particularly the sodium salts.
While such a chelating agents, particularly nitrogen containing chelating agents are generally recognized in the art as being effective in the removal of soap scum stains, there are growing environmental concerns attendant upon their use. The use of such chelating agents based on organic acid compounds, especially nitrogen containing organic compounds which include a plurality of carboxylic acid groups especially ethylenediamine mono-, di- or tri-acetic acid, ethylenediaminetetraacetic acids are desirably to be avoided.
According to a preferred aspect of the invention there is provided an alkaline ready to use cleaning and sanitizing composition which is essentially free of a chelating agent based on a nitrogen containing chelating agents, which composition is particularly adapted to be used as a xe2x80x98ready-to-usexe2x80x99 type composition, as well as in a non-pressurized container which is supplied with a hand pumpable trigger spray apparatus and which is particularly directed for the effective removal of soap scum stains on hard surfaces. The inventive composition comprises:
an amine oxide surfactant;
a nonionic alkoxylated alcohol surfactant;
a germicide constituent, preferably a germicidal cationic surfactant, and most preferably a water miscible or water soluble quaternary ammonium compound having germicidal properties;
organic solvent constituent, preferably a glycol ether;
an carbonate constituent, preferably an alkali metal or alkaline earth metal carbonate constituent;
an hydroxide constituent, preferably an alkali metal or alkaline earth metal hydroxide constituent;
optionally, a minor amount of one or more conventional additives including coloring agents, fragrances, opacificers, thickening agents, pH adjusting
agents, buffers; and,
water.
According to particularly preferred embodiments the total amounts of the surfactants do not exceed 2.0% wt., more desirably do not exceed 1.75%, and more preferably do not exceed 1.25% wt. It is a surprising and advantageous feature of the inventive compositions that very effective cleaning of soap scum, and sanitization of hard surfaces is achieved in such a ready to use composition which contains such a low level of surfactants and at the same time being essentially free of chelating agents based on organic acid compounds, especially nitrogen containing organic compounds and particularly those which include a plurality of carboxylic acid groups.
The compositions according to the invention include one or more amine oxide surfactants. Preferably the amine oxide surfactant may be represented by the following structure: 
wherein:
each R1 independently is a straight chained or branched C1-C4 alkyl group, but preferably both R1 are methyl groups; and, R2 is a straight chained or branched C8-C18 alkyl group, preferably is a C8-C12 alkyl group. Preferably, each of the R1 and R2 are straight chained. Technical grade mixtures of two or more amine oxides may be used, wherein amine oxides of varying chains of the R2 group are present. Particularly preferred are the amine oxides shown in the Examples.
The water dispersible amine oxide of the compositions of the invention is preferably present in an amount of from 0.25-0.75% wt., and more preferably is present in an amount of about 0.4-0.6% wt., based on the total weight of the composition.
The compositions of the invention include one or more nonionic alkoxylated alcohol surfactants. Suitable nonionic surfactants include condensation products of alkylene oxide groups with an organic hydrophobic compound, such as an aliphatic or alkyl aromatic compound.
Preferred nonionic surfactants are those based on the condensation product of one mole of an aliphatic alcohol having from 8 to 18 carbon atoms with from 1 to about 10 moles of alkylene oxide. These resultant reaction products include alkoxylated, especially ethoxylated and/or propoxylated linear alcohols as well as non-linear alcohols, and such alcohols expressly include primary, secondary as well as tertiary alcohols. Such materials are per se, known to the art.
Very preferably the nonionic surfactant is based an alkoxylated (ethoxylated, propoxylated) aliphatic linear fatty alcohol which is ethoxylated to a degree of from 6 to 12 moles of ethylene oxide per mole of alcohol. As known to the art, such materials are generally supplied as technical grade mixtures of one or more linear fatty alcohols which are predominantly ethoxylated. Most preferably the nonionic surfactant is based on alkoxylated linear C12-C16 aliphatic alcohol having an average of about 8-10 moles of ethoxylation per mol of alcohol, especially where such alcohols are primary alcohols. Such materials are presently commercially available as in the NEODOL series of alcohol ethoxylates (Shell Chem. Co.) as well as in the GENAPOL series of alcohol ethoxylates (Clariant Chem. Co.).
The inventive compositions also include a germicide constituent which is effective against gram positive bacteria or gram negative bacteria, but preferably against both. Desirably the germicide constituent is at least one cationic surfactant which is found to provide a broad antibacterial or sanitizing function. Any, cationic surfactant which satisfies these requirements may be used and are considered to be within the scope of the present invention, and mixtures of two or more cationic surface active agents, viz., cationic surfactants may also be used.
Examples of preferred cationic surfactant compositions useful in the practice of the instant invention are those which provide a germicidal effect to the concentrate compositions, and especially preferred are quaternary ammonium compounds and salts thereof, which may be characterized by the general structural formula: 
where at least one of R1, R2, R3 and R4 is a alkyl, aryl or alkylaryl substituent of from 6 to 26 carbon atoms, and the entire cation portion of the molecule has a molecular weight of at least 165. The alkyl substituents may be long-chain alkyl, long-chain alkoxyaryl, long-chain alkylaryl, halogen-substituted long-chain alkylaryl, long-chain alkylphenoxyalkyl, arylalkyl, etc. The remaining substituents on the nitrogen atoms other than the abovementioned alkyl substituents are hydrocarbons usually containing no more than 12 carbon atom. The substituents R1, R2, R3 and R4 may be straight-chained or may be branched, but are preferably straight-chained, and may include one or more amide, ether or ester linkages. The counterion X may be any salt-forming anion which permits water solubility of the quatemary ammonium complex.
Exemplary quaternary ammonium salts within the above description include the alkyl ammonium halides such as cetyl trimethyl ammonium bromide, alkyl aryl ammonium halides such as octadecyl dimethyl benzyl ammonium bromide, N-alkyl pyridinium halides such as N-cetyl pyridinium bromide, and the like. Other suitable types of quaternary ammonium salts include those in which the molecule contains either amide, ether or ester linkages such as octyl phenoxy ethoxy ethyl dimethyl benzyl ammonium chloride, N-(laurylcocoaminoformylmethyl)-pyridinium chloride, and the like. Other very effective types of quaternary ammonium compounds which are useful as germicides include those in which the hydrophobic radical is characterized by a substituted aromatic nucleus as in the case of lauryloxyphenyltrimethyl ammonium chloride, cetylaminophenyltrimethyl ammonium methosulfate, dodecylphenyltrimethyl ammonium methosulfate, dodecylbenzyltrimethyl ammonium chloride, chlorinated dodecylbenzyltrimethyl ammonium chloride, and the like.
Preferred quaternary ammonium compounds which act as germicides and which are particularly useful in the practice of the present invention include those which have the structural formula: 
wherein R2 and R3 are the same or different C8-C12 alkyl, or R2 is C12-C16 alkyl, C8-18 alkylethoxy, C8-18 alkylphenolethoxy and R3 is benzyl, and X is a halide, for example chloride, bromide or iodide, or is a methosulfate anion. The alkyl groups recited in R2 and R3 may be straight-chained or branched, but are preferably substantially linear.
Particularly useful quaternary germicides include compositions which include a single quaternary compound, as well as mixtures of two or more different quaternary compounds. Particularly useful quaternary germicides include which are a available under the tradenames BARQUAT, BARDAC, HYAMINE, BTC or LONZABAC (Each of these recited materials are presently commercially available from Lonza, Inc., Fairlawn, N.J. and/or from Stepan Co., Northfield Ill.) Particularly preferred are the quaternary ammonium compounds described in the Examples.
The germicidal constituent may be present in any effective amount, but generally need not be present in amounts in excess of about 5% wt. based on the total weight of the composition. The preferred germicidal cationic surfactant(s) may be present in the concentrated liquid disinfectant compositions in amounts of from about 0.001% by weight to up to about 0.5% by weight, preferably about 0.01-0.25% by weight, most preferably in amount of between 0.5-0.10% by weight.
The compositions of the invention include an organic solvent constituent.
Useful organic solvents are those which are at least partially water-miscible such as alcohols, water-miscible ethers (e.g. diethylene glycol diethylether, diethylene glycol dimethylether, propylent glycol dimethylether), water-miscible glycol ether (e.g. propylene glycol monomethylether, propylene glycol mono ethylether, propylene glycol monopropylether, propylene glycol monobutylether, ethylene glycol monobutylether, dipropylene glycol monomethylether, diethyleneglycol monobutylether), lower esters of monoalkylethers of ethyleneglycol or propylene glycol (e.g. propylene glycol monomethyl ether acetate) all commercially available such as from Union Carbide, Dow Chemicals or Hoescht. Mixtures of such organic solvents can also be used.
Particularly preferred as the organic solvent constituent in this invention are the glycol ethers having the general structure Raxe2x80x94Oxe2x80x94Rbxe2x80x94OH, wherein Ra is an alkoxy of 1 to 20 carbon atoms, or aryloxy of at least 6 carbon atoms, and Rb is an ether condensate of propylene glycol and/or ethylene glycol having from one to ten glycol monomer units. Preferred are glycol ethers having one to five glycol monomer units. These are C3-C20 glycol ethers. Examples of more preferred solvents include propylene glycol methyl ether, dipropylene glycol methyl ether, tripropylene glycol methyl ether, propylene glycol isobutyl ether, ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol butyl ether, diethylene glycol phenyl ether, propylene glycol phenol ether, and mixtures thereof. More preferably employed as the solvent is one or more of the group consisting of ethylene glycol n-butyl ether, diethylene glycol n-butyl ether, and mixtures thereof. Most preferably, the organic solvents are those which are described with reference to the Examples.
The organic solvent constituent, and especially the preferred glycol ether solvent, is preferably employed in an amount ranging from about 1-12% wt. based on the total weight of the composition.
The compositions of the invention are alkaline in nature, and may be exemplified as having a pH of at least 10 and higher, particularly a pH of 11 and higher, and especially at a pH of 12 and higher. It is generally required to include a minor but effective amount of an alkaline material in order to adjust the pH of the compositions to the desired alkaline pH. Conventional materials may be used including for example carbonates such as potassium carbonate, sodium bicarbonate and especially sodium carbonate. It is to be appreciated that the carbonate constituent aids in adjusting the alkalinity of the compositions, typically to a pH of about 11, but the use of an additional amount of a caustic may raise the pH to the preferred pH of 12 and above is normally required. This hydroxide constituent is provided in an amount which is found to be effective in facilitating the removal of soap scum stains from hard surfaces, particularly lavatory and kitchen surfaces. Good results are attained when the hydroxide constituent is present in an amount of from 0% wt. to about 0.2% wt., especially from 0.1% wt. to 0.2% wt. based on the total weight of the composition of which it forms a part.
The carbonate constituent is provided in an amount which is found to be effective in facilitating the removal of soap scum stains from hard surfaces, particularly lavatory and kitchen surfaces. Advantageously the carbonate constituent is present in an amount of from 2% wt. to about 7% wt., especially from 2% wt. to 5% wt. based on the total weight of the composition of which it forms a part.
The compositions of the invention show excellent efficacy in the removal of soap scum at high pHs, and do not deleteriously affect so called European enamel surface.
The inventive compositions optionally, but in certain instances desirably, may include a minor amount of one or more conventional additives including coloring agents, fragrances, opacificers, thickening agents, pH adjusting agents, buffers in addition to the required constituents described above. These further optional additives may be present in any combinations and in any suitable amount that is sufficient for imparting the desired properties to the compositions, and it is to be understood that in accordance with particularly preferred embodiments of the invention, the inventive compositions are essentially free of conventional chelating agents. These one or more conventional additives, when present, should be present in minor amounts, preferably in total comprise less than about 5% by weight of the compositions, and desirably less than about 3% wt.
As discussed above, in particularly preferred embodiments the inventive compositions are essentially free of chelating based on organic acid compounds, especially nitrogen containing organic compounds which include a plurality of carboxylic acid groups including ethylenediamine mono-, di- or tri-acetic acid, ethylenediaminetetraacetic acid. It is to be understood that by the term xe2x80x9cessentially freexe2x80x9d, the compositions comprise less than 0.05% wt. of the total composition, preferably less than 0.025% wt., and most preferably less than 0.01% wt. of such chelating agents.
As is noted above, the compositions according to the invention are largely aqueous in nature. Water is added to order to provide to 100% by weight of the compositions of the invention. The water may be tap water, but is preferably distilled and is most preferably deionized water. Desirably, the compositions of the invention comprise at least 78% wt. water, more desirably at least 80% wt., and most desirably comprise at least 82.5% water.
According to a particularly preferred aspect of the invention there is provided an alkaline ready to use cleaning and sanitizing composition which is essentially free of a chelating agent based on an organic acid compound, especially nitrogen containing chelating agents which composition which composition is particularly adapted to be used as a xe2x80x98ready-to-usexe2x80x99 type composition, as well as in a non-pressurized container which is supplied with a hand pumpable trigger spray apparatus and which is particularly directed for the effective removal of soap scum stains on hard surfaces which comprises:
0.4-0.6% wt. of an amine oxide surfactant, preferably a lauryl dimethyl amine oxide surfactant;
0.6-0.9% wt. of a nonionic alkoxylated alcohol surfactant;
0.05-0.1% wt. of a quaternary ammonium compound as a germicide constituent;
6-8% wt. of a glycol ether as an organic solvent constituent;
2-3% wt. a carbonate constituent;
0.1-0.2% wt. of a hydroxide constituent;
at least 80% wt., preferably at least 82% wt. water, and,
optionally, a minor amount of one or more conventional additives including coloring agents, fragrances, opacificers, thickening agents, pH adjusting agents, buffers;
wherein the total amounts of the surfactant constituents does not exceed 2.0% wt. It is a surprising and advantageous feature of the inventive compositions, that very effective cleaning of soap scum, and sanitization of hard surfaces is achieved in such a ready to use composition which contains such a low level of surfactants and at the same time being essentially free of chelating agents based on organic acid compounds, especially nitrogen containing organic compounds which include a plurality of carboxylic acid groups.
Such materials which may be used to produce the compositions according to the present invention are known to the art. For any particular composition, such optional ingredients should be compatible with the other ingredients present.
Such a hard surface cleaning composition according to the invention is desirably provided as a ready to use product which may be directly applied to a hard surface. Hard surfaces which are to be particularly denoted are those where soap scum are prone to be found, i.e., lavatory fixtures such as shower stalls, bathtubs and bathing appliances (racks, curtains, shower doors, shower bars) toilets, bidets, wall and flooring surfaces especially those which include refractory materials and the like. Further hard surfaces which are to be denoted are those associated with kitchen environments and other environments associated with food preparation, including cabinets and countertop surfaces as well as walls and floor surfaces. It is to be particularly noted that due to the alkaline characteristics of the inventive composition, the compositions taught herein are particularly useful in the cleaning and sanitization of so-called European porcelain surfaces.
The following examples below illustrate exemplary and preferred formulations of the compositions according to the invention.
Throughout this specification and in the accompanying claims, weight percents of any constituent are to be understood as the weight percent of the active portion of the referenced constituent, unless otherwise indicated.